As used herein, a head mounted device (HMD) is an electronic device worn by a user on, or otherwise coupled to, the user's head. In some embodiments, an HMD may contain, or be adapted to receive, a display that may be used to provide digital images and/or information to the user on a physical image plane of the HMD. For example, the images and/or information provided on the HMD display may completely immerse the user in digitally-generated surroundings, thereby providing the user with a Virtual Reality (VR) experience that simulates a different reality than the user's physical surroundings. In other embodiments, digital entities (e.g., images and/or information) may be projected towards the user's eye(s) to enhance what the user sees in their physical environment, thereby providing an Augmented Reality (AR) or Mixed Reality (MR) experience to the user. In AR/MR HMDs, a complex set of optics is often required to combine the projected digital entities with the images or light received from the user's environment.
Once the user dons an HMD, the user is often required to manually adjust the position of the HMD on the user's head until the user perceives that the digital images and/or information is in the user's field of view and in focus. This is a highly subjective, trial-and-error process that often requires a lot of “fiddling” on the user's part. It is, therefore, desirable to provide a more accurate method for adjusting a position of an HMD with respect to the user based on one or more measurements specific to the user.